Jointed rule



April 3, 1928.

C. W. HUMPHREY JoINTED RULE Filed June 12. 1925 rTOP/Yfy Patented Apr. 3, 1928.

UNITED STATES PATENT OFFICE.

j CLAYTON W. HUMTPHREY,`OF UNIONVILLE, CONNECTICUT.

' l yJoiiarrisio RULE.

.Application-mod .Tune 12, 1,825. Serial No. 36,743.

My invention relates to the class of measuring devices that are adaptedto be folded when not in use, and an object ot' my invention,`among others, isthe production .of a rule having a joint that is simple inv construction and possesses. ineansv for locating the blades in .different angular positions, said joint at the same time being compact and amply strong to resist the forces to which it is commonly subjected'l in use.

One form of a rule embodying my invention and in the construction and use of which the objects herein set out, as well as others, may be attained, is illustrated in the accompanying drawings, in which Figure 1 is a face view of a rule comprising several blades connected by my improved joint, the several blades being folded into closed position.

Figure 2 is an edge viewot the same.

Figure 3 is a detail sectional view, scale enlarged, through a portion of two blades and the pivot joint embodying my invention.

Figure 11 is a view similar to Figure 3 but of a single blade only showing one member of my improved joint.

Figure 5 is a face view of one end of a blade having one member of my improved joint secured thereto.

Figure 6 is a similar view, but showing the other member of the joint.

Figure 7 is a view in section on a plane denoted by the dotted line 77 of Figure 3.

Figure 8 is a view similar to Figure f1, but showing the other member of my improved joint.

While my invention is not especially limited in its application to any particular kind of a rule or similar device, yet as it is well adapted for use to connect l the blades of what is commonly known as a zigzag rule7 I havel selected such 'for the purpose of illustrating my invention in the drawings herein, in which the numerals 9 1() indicate two blades of a rule connected bya joint embodying my invention, a complete rule comprising several of said blades being shown in Figure 2, but the descriptionherein being confined to two blades only as sufficient for a clear understanding of the invention, it being understood that all of the joints may or may not embody my invention.

A hole 15 is formed in the hub 13 concentric with but larger in diameter' than a hole 16 extending through the blade 9. The other blade 10 has a hole of the same diameteras the hole 16 and a pawl plate 17 is secured in a recess 18 in the end of the blade similar to that at the end ot the blade 9, a pawl retaining recess 19 opening into said recess 18. In the specific form shown the plate 17 has a projection the edges of which are'struck up to constitute a flange to hold the loop, this projection being retained inthe recess in the blade andas shown in Figures 6, 7 and 8,01. the drawings. This plate 17 has a retaining hub 20 of a diameter to it the hole 16 in the plate 11, said hub being received in -said hole so that the end ot the hub may bear against the blade 9 at the bottom of the hole 15. A hole 21 is formed through the hub 20 of a size the same as the hole 16, said holes 16 and 21 being ot the diameter of a stud 22 that extends through said holes and that may be headed to rotatably join the plates 9 and 10.

Pawls 23 are formed at the ends of spring arms 24, said arms preferably comprising a single piece of wire bent into aretaining loop 25 at their joined ends, said loop being formed to fit within the recess 19 to be held therein, and the pawls 23 at the ends of said arms being formed to fit within the notches 14: comprising ratchet teeth in the positioninghub 13.

It will be understood that the joint composed o the members, as hereinbefore described, is very compact and that the blades are located at a minimum distance apart. The blades may be rotated one with respect to another by the application of a little force and when positioned with the pawls engaging the teeth of the ratchet the blades will be frictionally held with suiiicient rigidity for all of the purposes to which a r'ule of this character may be subjected.

In accordance with the provisions of the patent statutes I have described the principles ot operation o1 my invention, together with the device which I now consider to represent the best embodiment thereof, but I desire to have it understood that the device shown is only illustrative and that the invention may be carried out by other means and applied to uses othe'i than those above set out. f

I claim- 1. A blade, a plate secured thereto, a hub projecting from said plate, another blade, a plate secured thereto and having a recess to receive said hub, a pawl attached to said first named plate, a. ratchet attached to the last named `plate and having teeth to 'be engaged by said paWl, and means for pivot-- ally connecting said plates.,l p

2( A blade, a plate secured thereto and having a ratchet With ratchet teeth, a second blade, a platesecured thereto and having a recess, a paWl comprising branching arms with a loop at the joined portions of said arms located Within said recess, the ends of the arms comprising pawls to engage'said ratchet and means for ,pivotally connectingsaid plates.

3. blade, la plate secured thereto and having a hub with :ratchet teeth thereon and a hub receiving recess therein, -a second blade, a plate secured thereto and having a retaining 'hub Vto engage the recess in the rst mentioned hub, said last mentioned blade having a: pawl receivino comprising a `single piece ci:

recess, a pawl material bent into ya loop locatedin said-pawl receiving i recess, said pawl comprising branches the ends of which are formed to engage said ratchet teeth and means for pivotally connecting said plates.

4. A blade, a plate secured thereto,'a hub projecting from saidplate and having an opening therethrough, a `second blade, a plate secured `thereto and having a hub Wit-h an opening therethrough and a recess therein to receive the hub ofthe lirst mentionec CLAYTON W. HUMPHREY. 

